{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:51323"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:51323","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Squaric acid as a versatile compound in the design of molecular solids","abstract":"Within the scope of this present work the exploitation of the coordination modes of the squarate and also its acid properties were envisaged. In a systematic way, using either a coordinative or a hydrogen-bonding motif, three classes of compounds have been synthesized and characterized by single-crystal X-ray diffraction: 1. Hydrogen-bonded systems based on acid-base reactions of biguanide derivatives (N,N-dimethylbiguanide, N-phenylbiguanide, N-o-tolylbiguanide) and squaric acid. It is envisaged here the correlation between the pH of the media, the p-delocalization and hydrogen bond lengths. The shortest hydrogen bonds are present in very strong acidic media, due to the presence of the [SQH]- ([SQH]- = monohydrogensquarate) together with [BigH3]2+ ([BigH3]2+= biguanidinium). In these ions the p-delocalization is less pronounced than in [SQ]2- ([SQ]2- = squarate dianion) and [BigH2]+, ([BigH2]+ = monohydrogenbiguanidinium) which are present in basic media.2. Squarate complexes of transition metals. A dinuclear Cu(II)-squarate compound and a series of homo- and heteropolynuclear compounds with magnetically interesting cations have been obtained. The coordination modes of the squarate dianion are µ-1,2-bis(monodentate) in the dinuclear compound and µ-1,3-bis(monodentate) in polynuclear compounds.3. Ag(I)-squarate coordination polymers which combine the bridging ability of squarate with the flexibility in the coordination number, donor type and the geometry adopted by the AgI cation.","abstract_html":"Within the scope of this present work the exploitation of the coordination modes of the squarate and also its acid properties were envisaged. In a systematic way, using either a coordinative or a hydrogen-bonding motif, three classes of compounds have been synthesized and characterized by single-crystal X-ray diffraction: 1. Hydrogen-bonded systems based on acid-base reactions of biguanide derivatives (N,N-dimethylbiguanide, N-phenylbiguanide, N-o-tolylbiguanide) and squaric acid. It is envisaged here the correlation between the pH of the media, the p-delocalization and hydrogen bond lengths. The shortest hydrogen bonds are present in very strong acidic media, due to the presence of the [SQH]- ([SQH]- = monohydrogensquarate) together with [BigH3]2+ ([BigH3]2+= biguanidinium). In these ions the p-delocalization is less pronounced than in [SQ]2- ([SQ]2- = squarate dianion) and [BigH2]+, ([BigH2]+ = monohydrogenbiguanidinium) which are present in basic media.2. Squarate complexes of transition metals. A dinuclear Cu(II)-squarate compound and a series of homo- and heteropolynuclear compounds with magnetically interesting cations have been obtained. The coordination modes of the squarate dianion are µ-1,2-bis(monodentate) in the dinuclear compound and µ-1,3-bis(monodentate) in polynuclear compounds.3. Ag(I)-squarate coordination polymers which combine the bridging ability of squarate with the flexibility in the coordination number, donor type and the geometry adopted by the AgI cation.","abstract_has_math":false,"creators":["Serb, Mihaela Diana"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Englert, Ullrich"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2008,"date_issued":"2008","date_published":"2008","updated_at":"2026-07-30T19:40:33Z","subjects":["info:eu-repo/classification/ddc/540","Wasserstoffverbindungen","Quadratsäure","Polymerkomplexe","Chemie","Wasserstoffbrückenbindungen","Quadratat-Komplexe","Quadratat-Koordinationspolymere","squaric acid","hydrogen bonds","squarates","squarate coordination polymers"],"languages":["eng"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113626%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113626%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113626%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/51323","outbound_label":"Repository record","outbound_source":"dc:identifier"},"source_record":{"url":"https://publications.rwth-aachen.de/oai2d?verb=GetRecord&metadataPrefix=oai_dc&identifier=oai%3Apublications.rwth-aachen.de%3A51323","prefix":"oai_dc"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Englert, Ullrich"]},{"key":"dc:creator","label":"Author","values":["Serb, Mihaela Diana"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2008"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-28780"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/540","Wasserstoffverbindungen","Quadratsäure","Polymerkomplexe","Chemie","Wasserstoffbrückenbindungen","Quadratat-Komplexe","Quadratat-Koordinationspolymere","squaric acid","hydrogen bonds","squarates","squarate coordination polymers"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/51323","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113626%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Within the scope of this present work the exploitation of the coordination modes of the squarate and also its acid properties were envisaged. In a systematic way, using either a coordinative or a hydrogen-bonding motif, three classes of compounds have been synthesized and characterized by single-crystal X-ray diffraction: 1. Hydrogen-bonded systems based on acid-base reactions of biguanide derivatives (N,N-dimethylbiguanide, N-phenylbiguanide, N-o-tolylbiguanide) and squaric acid. It is envisaged here the correlation between the pH of the media, the p-delocalization and hydrogen bond lengths. The shortest hydrogen bonds are present in very strong acidic media, due to the presence of the [SQH]- ([SQH]- = monohydrogensquarate) together with [BigH3]2+ ([BigH3]2+= biguanidinium). In these ions the p-delocalization is less pronounced than in [SQ]2- ([SQ]2- = squarate dianion) and [BigH2]+, ([BigH2]+ = monohydrogenbiguanidinium) which are present in basic media.2. Squarate complexes of transition metals. A dinuclear Cu(II)-squarate compound and a series of homo- and heteropolynuclear compounds with magnetically interesting cations have been obtained. The coordination modes of the squarate dianion are µ-1,2-bis(monodentate) in the dinuclear compound and µ-1,3-bis(monodentate) in polynuclear compounds.3. Ag(I)-squarate coordination polymers which combine the bridging ability of squarate with the flexibility in the coordination number, donor type and the geometry adopted by the AgI cation."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University 155 S. (2008). = Aachen, Techn. Hochsch., Diss., 2008"]},{"key":"dc:title","label":"Title","values":["Squaric acid as a versatile compound in the design of molecular solids"]}]}],"canonical_facts":{"dc:contributor":["Englert, Ullrich"],"dc:coverage":["DE"],"dc:creator":["Serb, Mihaela Diana"],"dc:date":["2008"],"dc:description":["Within the scope of this present work the exploitation of the coordination modes of the squarate and also its acid properties were envisaged. In a systematic way, using either a coordinative or a hydrogen-bonding motif, three classes of compounds have been synthesized and characterized by single-crystal X-ray diffraction: 1. Hydrogen-bonded systems based on acid-base reactions of biguanide derivatives (N,N-dimethylbiguanide, N-phenylbiguanide, N-o-tolylbiguanide) and squaric acid. It is envisaged here the correlation between the pH of the media, the p-delocalization and hydrogen bond lengths. The shortest hydrogen bonds are present in very strong acidic media, due to the presence of the [SQH]- ([SQH]- = monohydrogensquarate) together with [BigH3]2+ ([BigH3]2+= biguanidinium). In these ions the p-delocalization is less pronounced than in [SQ]2- ([SQ]2- = squarate dianion) and [BigH2]+, ([BigH2]+ = monohydrogenbiguanidinium) which are present in basic media.2. Squarate complexes of transition metals. A dinuclear Cu(II)-squarate compound and a series of homo- and heteropolynuclear compounds with magnetically interesting cations have been obtained. The coordination modes of the squarate dianion are µ-1,2-bis(monodentate) in the dinuclear compound and µ-1,3-bis(monodentate) in polynuclear compounds.3. Ag(I)-squarate coordination polymers which combine the bridging ability of squarate with the flexibility in the coordination number, donor type and the geometry adopted by the AgI cation."],"dc:identifier":["https://publications.rwth-aachen.de/record/51323","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113626%22"],"dc:language":["eng"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-28780"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University 155 S. (2008). = Aachen, Techn. Hochsch., Diss., 2008"],"dc:subject":["info:eu-repo/classification/ddc/540","Wasserstoffverbindungen","Quadratsäure","Polymerkomplexe","Chemie","Wasserstoffbrückenbindungen","Quadratat-Komplexe","Quadratat-Koordinationspolymere","squaric acid","hydrogen bonds","squarates","squarate coordination polymers"],"dc:title":["Squaric acid as a versatile compound in the design of molecular solids"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:40:33Z"}